How the Body Works : Anatomy of the Hypothalamus

Connected by many nerve tracts with the brain and spinal cord, the hypothalamus acts as a link between the endocrine system and the nervous system. It functions automatically, monitoring and regulating the autonomic nervous system as well as the state of the body's metabolism through eating, drinking, temperature control, sexual drives and
"fight or flight" reactions. It also controls the menstrual cycle and is thought to contain a pleasure center. Finally, it directs hormones released by the anterior pituitary gland.

The anatomy of the hypothalamus includes:

The medial forebrain nerve bundle, which leads to the front area of the cerebral cortex.

The fornix, a bundle of nerve fibers, which carries messages associated with memory from the limbic system.

The "control centers", which are grouped together to form the core of the hypothalamus.

The mamillothalamic tract, which is involved with the synthesis of emotions.

The dorsal longitudinal bundle, which carries messages concerned with digestion to the brain stem.

The pituitary portal system, which carries hypothalamic hormones to the anterior pituitary gland.

The infundibular stalk, which connects the pituitary gland to the brain.

The neurosecretory tracts, which channel hypothalamic hormones to the posterior pituitary gland, and the hypothalamic artery, which conducts oxygenated blood to the hypothalamus.

Directly below the hypothalamus lies the anterior and posterior pituitary glands. The anterior pituitary gland secretes hormones under the control of the hypothalamus.